Improvement in apparatus for making pulp or paper-stock from wood



. M. R. FLETCHER. Y. Apparatus for Making Pulp or Paper Stock from"`Wood, 8vo.

Patented Oct. 23, 1877.

N,P'e1"aRs. Pnoro kan, WASHINGTON, D c.

UNITED STATES PATENT OFFICE.

MOORE R. FLETCHER, OF CONCORD, NEW HAMPSHIRE.

IMPROVEMENT lN APPARATUS FORMAKING PULP OR PAPER-STOCK FROM WOOD, &c.

Specification forming'part of Letters Patent No. 196,515, dated October23, 1877 application lcd October 10, 1877.

To all whom it may concern:

Beitknownthatl,MooEERUssELLFLETcH- ER, of the city of Concord, county ofMerrimack, and State of New Hampshire, have invented a new and usefulImprovement for Converting Fibrous Vegetable Matter into Paper Stock orPulp; and I do hereby declare the following to be such an exactdescription of the same as will enable others skilled in the art to makeand use the same, reference being had to the accompanying drawings,andto the letters of reference marked thereon, similar lettersindicating corresponding parts in the diiferent figures, of which-Figure 1 shows the arrangement of a series of machines consisting of themachine for cutting the material into shreds or shavings, followed bythe digesting-tank, so placed that the stock from the cutting-machine iseasily discharged into this tank, which is followed by a mill, whichfurther reduces the ber, and is in turn followed by a pulping-en gine,which reduces the material to a proper consistency to be used aspaper-stock, or any of the various uses to which such pulp maybeapplied. Fi g. 2 shows the conical serrated runner of the grinding orcrushing mill. Fig. 3 represents a sectional view of the case by whichthe runner is inclosed. Fig. 4 is a partial plan-view of the corrugatedconcave bed-plate used in the pulpengine. Fig. 5 shows the arrangementof the platesin each blade. Fig. 6 represents a modi- -iication of thesame. D, Fig. l, shows the arrangement of the blades in the pulp-en gineroll and their adaptation to the bed-plate; and Fig. 7 shows one of theshreds or shavings of wood produced by the cutting-machine.

The object of this invention is to reduce the cost of producing pulp orpaper-stock from v iibrous vegetable matter, and at the same timefurnish as good or a better article than has been heretofore producedbythe machines and processes in common use for that purpose; and theinvention consists in the construction of the machines and the varioussteps of the process, as will be hereinafter fully set forth, and thenspecifically pointed out in the claims.

The` materials adapted for making pulp or paper-stock by my improvedapparatus are wood and other vegetable substances of av fibrous nature.v

For working wood, I construct a machine for making shreds or shavingsrapidly, which are peculiarly adapted for after treatment, in thefollowing manner: I make aframe, A, of wood or iron, about two and ahalf feet high, four and a half feet long, and from one and a half totwo and a half feet wide. On this frame l arrange an iron shaft, a,three or more inches in diameter, carrying a suitable driving-pulley orother mechanism for producing rotation, and on which, near one side of'the frame, is attached an iron cutter-head, b, from two to four feet indiameter, and half an-inch or more in thickness, and provided withopenings or slots, in which are securely fastened two or more knives orblades, c, which are made adjustable Vto re gula-te the thickness of theshaving desired by means of set-screws. rIhey are also so arranged onthe cutter-head-that they cut from the outer end of the blade toward theinner end, and are adapted. to cut shavings varying in thickness fromone-eighth of an inch to an inch. The piece of wood to be reduced toshavings is held against the cutter at an angle, so that the shavingsare cut shearing` from the stick.

Near the cutter-head on the same shaft may be attached a balance-wheelof from four to ve feet in diameter, and of sufcient weight to overcomethe resistance of the material to be cut. The cutter-head,balance-wheel, and pulley may be cast all in one piece; but I prefer tomake them in separate pieces and securely attached to the shaft a. Thepulley Amay be made of any diameter and kwidth of face desired,ordinarily of four to eight inches face, and of a diameter equal toone-half of the diameter of the balance-wheel.

I take any kind of forest trees, in cord-wood dimensions for ease inhandling, and hold one end against the cutter-head and apply pressure bythe hand or otherwise. As the cutterhead revolves the shavings are cutdiagonally to the grain from the end of the stick, and from the positionin which the stick of wood is held the fibers of the shaving are muchlonger than its thickness. These shavings, hav- Ving been cut by a thickknife or blade, are

shattered or broken, as seenin Fig. 7 ,by which they are peculiarlyfitted for after treatment.

In making pulp or paper-stock of fibrous other ibrous shru ditionconvenient for handling, which is done material it is of greatimportance to have all the bers of u wi m length. This result is se-Icured by my method of cutting the shavin gs. The second pait of myprocess consists in reducing cane-biz kes, palm, palmetto, and

l s of coarse growth to a conby passing them between rollers, therebyreducing them to 2 tate in which they may be passed through a hay or ragcutter of ordinary construction.

The shavings or other stock for treatmentare put into the tank B, Fig.l, which is filled twothirds full of water, in which are dissolved andthoroughly mixed (say, for every tou of stock) ten pounds to fiftypounds of soda-ash, or from six pounds to thirty pounds of potash, vwithfrom two pounds to five pounds of chloride of lime, o1 slake from half abushel `to a bush el an l a h alf of -fresh lime with from three poi 1rs to e ght pounds of chloride of lime, accor l n to 'he kind of stockunder treat ment and th n i of pulp to be made.

u eitherof the above alkalies or the Lr alent separately in variedproportion 'ing ascertained that the bond of unim in ctrl le matter ismore speedily and sucsfullv broken down or softened byweak alies under alow degree of heat than by caustic or strong alkalies applied under 1 rissure with higher temperature. The resinous stocks require strongeralkalies and longer cooking or steaming than the non- Qq ha resinous.

I use alkalies varying in strength, from oneeighth of one degree to oneand one-fourth de-` gree.

In the treatment of non-resinous stockeither wood, straw, corn-stalks,or shrubs-the chloride of lime may be omitted with equal rel sults.

I do not require causticity of alkali for softening resinous,albuminous, silicious, or nitrogenous matter, as is ordinarily used. Acover is provided for the tank, to confine the heat, which is addedslowly by steam or otherwise, until it reaches 1300 or 14.00, and keptat that point from two to four hours. The heat may then be increased tothe boilingpoint, and kept there for six hours, or longer, according tothe kind of stock under treat- The liquid is then removed, and may beused several times by adding a little more chemicals.

The stock is then removed through a door in the tank d, andpassed"through a grinding or crushing machine, C, yconstructed asfollows: This machine is made of a male cone, c, and female cone or casej', with grooves cut close together, or elevations on both the male andfemale cone, and extending diagonally from the top to the lower edge, sothat the motion of the male or inner cone, in its revolutions, will tendto carry the liber along their course through the machine. I

The last part of my process consists in pass- ".Ilhe bed plate of thispulp engine is from thirty-six to forty inches, or more, wide, insteadof six or eight inches, ordinarily used. I make it of iron or steelplates, from oneeighth of an inch to half an inch in thickness, withlead, leather, or other hard substance between every two of them. I alsomake it of stone, that will not readily polish in water. I also make itof chilled cast-iron, with corrugated elevations about one-third of aninch high, and one-third of an inch apart, extending over the entiresurface of the bed-plate in a zigzag' form from the riser nearly to theback-fall.

to represent the plates, or cast-iron elevations, as seen in thedrawing'.

The peculiar construction of this bed-plate or zigzag arrangement of thecorrugations insures equable wear of the blades in the roll, as well asthe more speedy and perfect reduction ofthe material operated upon, theangles in the corrugations being so diversified over the whole surfaceof the plate that the wear upon the blades is equal at all points, whilethose bed-plates having their angles arranged on lines from the risertoward the back-fall, crossing the blades at fixed points, will soonwear depressions in and greatly injure the blades.

The bed-plate is placed in its position by removing the midfeather andadjusting it from the inside of the tub.

For the pulp-engine E, I make the blades -thick on their outer edge, andalso of three or more plates of iron or steel in each blade, with leador other hard substance between every two of them, as seen in Figs. 5and 6, and securely fastened by rivets 7c.

My roll is securedV upon a shaft of iron in the ordinary manner, withiron heads and center, but with the grooves for holding the blades intheir position on a slant backward from the center of the roll. Theseblades are confined in the roll in the ordinary way by iron hoops l.

As the blades h are composed of several plates, and pass over thebed-plate thirty-six.

or forty inches wide, with elevations or grooves about three to theinch, every plate in each blade is made to press upon or rub over everyelevation or groove on the bed-plate; and it is clearly evident that therubbing or disintep gratin g is more extensive and perfect than can bedone by the single blade over the ordinary narrow bed-plate.

I am awa-re that it is not new to make paperpulp from shavings orcuttings of wood, and other iibrous materials, digested under greatpressure and heat in caustic alkali. Neither is it new to reduce theseiibrous materials to pulp in an ordinary rag-engine. These I do notbroadly claim; but

What I do claim as new, and desire to secure by Letters Patent, is thefollowing:

l. A cutting-machine for reducing wood to The stone bed-plate is groovedin a manner y shavings for making pulp, consisting of a disk orcutter-head provided with adjustable knives placed obliquely to itsradius, in combination with the devices shown for imparting rotationthereto, substantially as specified.

2. In the manufacture of pulp or paper-stock from wood or other fibrousmaterial, the digesting-vat in which the material is treated, incombination with the grinder and pulpingengine, all constructed,arranged, and operating substantially as and for the purpose specified.

3. In a pulping-engine, the removable bedplate, provided with a seriesof corrugations,

arranged in the manner herein shown and described, in combination with arubbing or grinding roll, substantially as specified.

4. In a machine for making pulp or paperstock, the disintegrating orrubbing roll, pro- MOORE RUSSELL FLETCHER.-

Witnesses: J. C. TAsKER, FRED. E. TAsKER.

